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The last avalanche forecast for the 2018/2019 season was posted on Sunday April 21st. Thank you to all who have supported the avalanche center through volunteer hours, field observations, and financial support.

Use this page to view archived advisories. The table below shows the overall danger rating and the bottom line for the 20 most recent advisories. Click on the time and date link above each danger rating icon to view the full advisory for that day. Use the date chooser or the pager at the bottom to scroll through the older advisories.

Near and above treeline pockets of MODERATE avalanche danger may exist on slopes 35 degrees and steeper on NW-N-NE-E-SE aspects due to newly formed wind slabs. In wind protected areas below treeline and in wind scoured areas near and above treeline, avalanche danger remains LOW.

Pockets of MODERATE avalanche danger may exist near and above treeline on NW-N-NE-E-SE aspects due to lingering unstable wind slabs on slopes 35 degrees and steeper. In wind protected areas below treeline and in wind scoured areas near and above treeline, avalanche danger is LOW.

Avalanche danger is MODERATE with pockets of CONSIDERABLE avalanche danger near and above treeline on NW-N-NE-E-SE aspects due to unstable wind slabs on slopes 35 degrees and steeper. In wind protected areas below treeline and in wind scoured areas near and above treeline, avalanche danger is LOW.

MODERATE avalanche danger exists on slopes 35 degrees and steeper on all aspects in near and above treeline terrain due to new wind slabs, the formation of loose wet snow, and unlikely but not impossible deep persistent slabs. MODERATE avalanche danger also exists below treeline on slopes 35 degrees and steeper on the SE-S-SW-W aspects due to the formation of loose wet snow.

MODERATE avalanche danger exists on slopes 35 degrees and steeper on all aspects in near and above treeline terrain due to wind slabs, the formation of loose wet snow, and unlikely but not impossible deep persistent slabs. MODERATE avalanche danger also exists below treeline on slopes 35 degrees and steeper on the SE-S-SW-W aspects due to the formation of loose wet snow. Although they are becoming more difficult to trigger, large, deep, and destructive avalanches could still occur today.

CONSIDERABLE avalanche danger exists on slopes 32 degrees and steeper on all aspects above 7000 ft. due to wind slabs, storm slabs, and deep persistent slabs resting on a variety of weak layers. Below 7000 ft. where more of the storm's precipitation fell as rain, less avalanche danger exists. Even though the best window for natural avalanches has passed, human triggered avalanches remain likely today. Large, deep, and destructive avalanches could still occur today.

Near treeline and above treeline, avalanche danger remains HIGH on NW-N-NE-E-SE aspects on slopes 32 degrees and steeper. For all other areas, avalanche danger is CONSIDERABLE on slopes 32 degrees and steeper. Wind slab, storm slab, and deep persistent slab avalanches are all possible today.

Near treeline and above treeline, avalanche danger is HIGH on NW-N-NE-E-SE aspects on slopes 32 degrees and steeper. For all other areas, avalanche danger is CONSIDERABLE on slopes 32 degrees and steeper. Wind slab, storm slab, wet slab, loose wet, and deep persistent slab avalanches are all possible today.

Areas of MODERATE avalanche danger will form today near and above treeline on the NW-N-NE-E-SE aspects on slopes 35 degrees and steeper as wind slabs continue to build. As higher intensity precipitation impacts the forecast area this evening through the overnight hours, avalanche danger is expected to increase to HIGH danger.

MODERATE avalanche danger exists on slopes steeper than 35 degrees at all elevations on the NW-N-NE aspects and on near and above treeline E-SE aspects. A combination of wind slabs resting on weak snow, old persistent slabs, and loose snow sluffs represent the main avalanche problems today. Human triggered avalanches could be possible today.

The avalanche danger remains LOW at all elevations and on all aspects. Even though avalanches have become unlikely on a regional scale, some unstable snow could still lurk on isolated terrain features or in extreme terrain.

The avalanche danger remains LOW at all elevations and on all aspects. Even though avalanches have become unlikely on a regional scale some unstable snow could still lurk on small isolated terrain features or in extreme terrain.

Avalanche danger is LOW for all elevations and aspects. Keep in mind that the definition of LOW danger states that human triggered avalanches are unlikely on a regional scale but could still occur in isolated areas or extreme terrain.

Avalanche danger is LOW for all elevations and aspects. Keep in mind that the definition of LOW danger states that human triggered avalanches are unlikely on a regional scale but could still occur in isolated areas or extreme terrain.

Pockets of MODERATE avalanche danger exist at all elevations on NW-N-NE aspects on slope steeper than 32 degrees that held snowcover prior to the recent snowfall. For all other areas, avalanche danger is LOW. Persistent slabs and wet slabs remain an ongoing avalanche concern.

Pockets of CONSIDERABLE avalanche danger may still exist on slopes steeper than 30 degrees in near and below treeline terrain on NW-N-NE aspects above 9000 ft. due to recent snow slabs sitting on top of persistent weak layers. Human triggered avalanches could remain likely on these slopes today. MODERATE avalanche danger exists on similar slopes on those aspects below 9000 ft. due to buried wet persistent weak layers. MODERATE avalanche danger also exists and on the wind loaded NW-N-NE-E-SE aspects steeper than 35 degrees in near and above treeline terrain due to the presence of wind slabs.

The unusual conditions that exist in the mountains right now require extra caution and superb travel skills.

HIGH avalanche danger exists on slopes steeper than 30 degrees in near and below treeline terrain on NW-N-NE aspects due to new heavy snow slabs sitting on top of persistent weak layers. Natural and human triggered avalanche are very likely on these slopes today. CONSIDERABLE avalanche danger exists on the wind loaded NW-N-NE-E-SE aspects in near and above treeline terrain due to the pressence of newly formed wind slabs on slopes 35 degrees and steeper. MODERATE avalanche danger exists on all other aspects.

Travel in, around, or near avalanche terrain is not recommended today.

Avalanche danger remains LOW for most areas today. In areas where rain falls on the snowpack, pockets of MODERATE danger could form on NW-N-NE-E aspects on slopes steeper than 37 degrees due to the possibility of loose wet avalanches.

The avalanche danger will increase tonight and tomorrow as a strong winter storm brings wind, some rain, and 1-2 ft of snow above 7000 ft. The new load on top of the already weak snowpack should cause the avalanche danger to reach HIGH meaning that natural and human triggered avalanches will become very likely tonight and tomorrow. Travel in and around avalanche terrain is not recommended tonight or during the day tomorrow.

For today, avalanche danger is generally LOW. Pockets of MODERATE danger may form on NW-N-NE-E aspects on slopes 37 degrees and steeper due to rain on snow. Areas where light rain falls on sugary, faceted surface snow hold the greatest possibility of loose wet avalanches. Rain may fall as high as 8,000' to 9,500' across the forecast area today. Snow level will generally be higher in the southern half of the area. Avalanche danger is generally nonexistent on SE-S-SW-W aspects due to the lack of snow cover.

An increase in avalanche danger my occur tonight into tomorrow. For today avalanche danger remains LOW at all elevations on snow covered NW-N-NE-E aspects. Avalanche danger is generally nonexistent on SE-S-SW-W aspects due to the lack of snow cover. The possibility of rain on snow tonight has the potential to increase avalanche danger. Depending on how much rain reaches the ground, natural wet loose snow avalanches could occur late tonight and early tomorrow morning.

Avalanche danger remains LOW on snow covered NW-N-NE-E aspects. Overall, triggering an avalanche has become unlikely, but a few small areas of unstable snow may still exist on isolated terrain features. The avalanche danger on SE-S-SW-W aspects remains nonexistent due to a lack of snow. Brandon will update the advisory by Tuesday at 7am.

Avalanche danger remains LOW on snow covered NW-N-NE-E aspects. A few small areas of unstable snow may still exist on isolated terrain features. The avalanche danger on SE-S-SW-W aspects remains nonexistent due to a lack of snow.

Avalanche danger remains LOW on snow covered NW-N-NE-E aspects. A few small areas of unstable snow may still exist on isolated terrain features. On SE-S-SW-W aspects a lack of snow makes the avalanche danger generally nonexistent.

Avalanche danger is LOW for all elevations on snow covered NW-N-NE-E aspects. Encountering an isolated area of unstable snow has become unlikely, but may still be possible due to the variability that can exist on a regional scale. Due to melt, avalanche danger on SE-S-SW-W aspects is generally nonexistent.

Avalanche danger is LOW for all elevations on snow covered NW-N-NE-E aspects. Human triggered avalanches are unlikely at this time. Encountering an isolated area of unstable snow has become unlikely, but may still be possible due to the variability that can exist on a regional scale. Due to melt, avalanche danger on SE-S-SW-W aspects is generally nonexistent.

Avalanche danger is LOW at all elevations on snow covered NW-N-NE-E aspects. Human triggered avalanches are unlikely but not impossible. Isolated areas of unstable snow may exist on isolated terrain features. Due to melt, avalanche danger on SE-S-SW-W aspects is generally nonexistent.

The avalanche danger has returned to LOW on all snow covered slopes. Human triggered avalanches are unlikely today but not impossible. Some unstable snow may continue to lurk on isolated terrain features. The SE-S-SW-W aspects do not have enough snow cover on them to warrant a danger rating.

The avalanche danger is LOW for most areas with consistent snow cover and nonexistent for areas without snow. On a few of the near treeline NW-N-NE aspects that received the most snow yesterday, some pockets of MODERATE avalanche danger may exist where human triggered avalanches may be possible on slopes steeper than 32 degrees. These more fragile areas are mostly likely to exist where small wind slabs formed above persistent weak layers.

This morning the avalanche danger remains LOW for areas with consistent snow cover. As snow and wind impact the region some pockets of MODERATE avalanche danger may form on near and above treeline NW-N-NE-E-SE aspects steeper than 32 degrees. The most likley places where human triggered avalanches could become possible are the near treeline NW-N-NE aspects where the wind slabs could sit on top of persistent weak layers.

The avalanche danger has dropped to LOW on all snow covered slopes due to a shrinking snowpack. Human triggered avalanches are unlikely today but not impossible. Some persistent slabs may continue to lurk on isolated terrain features. The SE-S-SW-W aspects do not have enough snow cover on them to warrant a danger rating.

Pockets of MODERATE avalanche danger may still exist on near and below treeline NW-N-NE aspects steeper than 32 degrees where consistent snow cover exists. Persistent slabs continue to lurk in these areas. Human triggered avalanches remain possible in these places. Lack of snow in all other areas has made the avalanche danger LOW or non-existent.

Some pockets of MODERATE avalanche danger still exist on near treeline and below treeline NW-N-NE aspects steeper than 32 degrees where consistent snow cover exists. Persistent slabs continue to lurk in these areas. Human triggered avalanches remain possible where these pockets MODERATE avalanche danger still exist. Lack of snow in all other areas has made the avalanche danger LOW or non-existent.

Pockets of MODERATE avalanche danger remain near treeline and below treeline on NW-N-NE aspects on slopes steeper than 32 degrees with consistent snow cover. This is due to lingering persistent slabs. In these areas, the possibility of human triggered avalanches remains ongoing. For all other areas avalanche danger is either LOW or non-existent due to the lack of snow cover.

Pockets of MODERATE avalanche danger remain near and below treeline on NW-N-NE aspects on slopes steeper than 32 degrees with consistent snow cover due to lingering persistent slabs. In these areas, the possibility of human triggered avalanches remains ongoing. For all other areas avalanche danger is either LOW or non-existent due to the lack of snow cover.

Pockets of MODERATE avalanche danger remain near and below treeline on NW-N-NE aspects on slopes steeper than 32 degrees where consistent snow cover exists. Lingering persistent slabs are keeping the possibility of human triggered avalanches ongoing in certain areas near treeline and below treeline on NW-N-NE aspects. For all other areas avalanche danger is either LOW or non-existent due to the lack of snow cover.

Current conditions are very conducive to human triggered avalanches. Use low angle (sub 30 degree) slopes for protection. Stay clear of areas connected to steeper slopes above. Conservative terrain choices and effective communication are critical given the current instability.

MODERATE avalanche danger continues near treeline and below treeline on NW-N-NE aspects on slopes 32 degrees and steeper due to ongoing instability of persistent slabs.

Human triggered avalanches remain possible. Pay attention to the big picture of surrounding terrain and the presence of steeper slopes above. Understand that remote triggering of avalanches from low angle slopes below to steeper slopes above is very possible under the current snowpack conditions.

On slopes steeper than 32 degrees, MODERATE avalanche danger exists on near and below treeline NW-N-NE aspects due to lingering persistent slabs. Human triggered persistent slabs remain possible. Remotely triggered avalanches can occur under these conditions. Some isolated areas of unstable snow may still remain on above treeline slopes as well.

In addition to the avalanche danger a myriad of season-ending obstacles still lurks just below the surface. Conservative terrain selection, careful snowpack evaluation, and conservative decision-making are essential.

On slopes steeper than 32 degrees, MODERATE avalanche danger exists on near and below treeline NW-N-NE aspects due to lingering persistent slabs. Some isolated areas of unstable snow may still remain on above treeline slopes as well. Human triggered persistent slabs remain possible in near and below treeline terrain. Remotely triggered avalanches can occur under these conditions.

In addition to the avalanche danger a myriad of season-ending obstacles still lurks just below the surface. Conservative terrain selection, careful snowpack evaluation, and conservative decision-making are essential.

On slopes steeper than 30 degrees, MODERATE avalanche danger exists at all elevations on NW-N-NE aspects an on the near and above treeline E-SE aspects due to a combination of widespread persistent slabs and lingering wind slabs. Human triggered persistent slabs remain possible in near and below treeline terrain. Remotely triggered avalanches can occur under these conditions. In addition to the avalanche danger a myriad of season-ending obstacles still lurks just below the surface. Conservative terrain selection, careful snowpack evaluation, and conservative decision-making are essential.

CONSIDERABLE avalanche danger exists in near and below treeline terrain on NW-N-NE aspects 30 degrees and steeper due to widespread persistent slabs. Human triggered persistent slabs remain likely today in near and below treeline terrain. Remotely triggered avalanches can occur under these conditions. MODERATE avalanche danger remains on the near and above treeline NW-N-NE-E-SE aspects due to lingering wind slabs. In addition to the avalanche danger a myriad of season-ending obstacles still lurks just below the surface. Conservative terrain selection, careful snowpack evaluation, and conservative decision-making are essential.

Widespread areas of CONSIDERABLE avalanche danger exist near and above treeline on NW-N-NE-E-SE aspects 30 degrees and steeper due to newly formed wind slabs and below treeline on NW-N-NE aspects 30 degrees and steeper due to persistent slabs. Natural avalanches are possible, human triggered avalanches are likely today. Significant avalanche danger exists below treeline. --- Everyone is chomping at the bit to get out there today. Only a small percentage have a handle on the weakness of the existing snowpack and the reality of avalanches today. Conservative terrain selection and effective group communication are imperative.

The snowpack is slowly building. At this time we are still without sufficient snow cover to warrant daily avalanche advisories. We are making snowpack observations and posting them to the observations page.

Fall storms are starting to impact the forecast area with rain and high elevation snow returning to the Sierra. The operational portion of the avalanche center has yet to brush off the dust accumulated during the summer hiatus. As mid/late October approaches, work will resume to get the operational program ready to issue regular avalanche advisories once conditions warrant.

The non-profit fundraising portion of the avalanche center has been hard at work organizing fall events. Take a look at the SAC calendar for upcoming events to fuel your excitement.

We have stopped issuing daily avalanche advisories for the 2012-2013 season. Avalanche advisories will resume in fall of 2013. The avalanche danger can and will change quickly this spring. Continue to monitor changing conditions and use caution when traveling in the backcountry. For general spring avalanche information read the full spring avalanche statement.

Early this morning, avalanche danger is LOW for all elevations and aspects. As the day progresses, areas of MODERATE danger will form on all aspects at all elevations on slopes 37 degrees and steeper in response to daytime warming. Small human triggered loose wet avalanches will become possible.

Early this morning, avalanche danger is LOW for all elevations and aspects. As the day progresses, areas of MODERATE danger will form on all aspects at all elevations on slopes 37 degrees and steeper in response to daytime warming. Small human triggered loose wet avalanches will become possible.

Early this morning, avalanche danger is LOW for all elevations and aspects. As the day progresses, areas of MODERATE danger will form on all aspects at all elevations on slopes 37 degrees and steeper in response to daytime warming. Small human triggered loose wet avalanches will become possible.

Small pockets of MODERATE avalanche danger may exist on near and below treeline slopes steeper than 35 degrees that received rain last night and this morning. Daytime warming may also cause small shallow wet snow instabilities to form.

This morning the avalanche danger is LOW. As the day warms up, small pockets of MODERATE avalanche danger may form on E-SE-S-SW-W aspects on slopes 35 degrees and steeper due to daytime warming creating small shallow wet snow instabilities.

Near and above treeline, very isolated pockets of MODERATE avalanche danger exist on E-SE-S-SW-W-NW aspects on slopes 35 degrees and steeper due to small shallow wind slabs. For all other areas, avalanche danger remains LOW.

Near and above treeline, areas of MODERATE avalanche danger exist on NW-N-NE-E-SE aspects on slopes 35 degrees and steeper due to newly formed wind slabs. For all other areas, avalanche danger remains LOW.

For most of today, avalanche danger will remain LOW for all elevations and aspects. Very isolated pockets of lingering wind slab may exist in recently wind loaded areas above treeline. After 5 pm today, pockets of MODERATE avalanche danger are expected to form in near treeline and above treeline terrain mainly on N-NE-E aspects as additional snowfall and wind create new wind slabs.

Both above and below treeline, MODERATE danger will form on all aspects and elevations on slopes 35 degrees and steeper due to daytime warming. Human triggered loose wet avalanches remain possible today.

Both above and below treeline, CONSIDERABLE danger will form quickly today on all aspects and at all elevations on slopes 35 degrees and steeper due to loose wet snow avalanches. Shallow naturally occurring loose wet avalanches are expected. Human triggered loose wet avalanches of greater size are likely.

Above 7,000', avalanche danger is MODERATE on all aspects on slopes 35 degrees and steeper due to a mix of storms slabs and wind slabs. Below 7,000', avalanche danger is LOW with pockets of MODERATE danger on all aspects on slopes 35 degrees and steeper due to the possibility of human triggered loose wet avalanches.

Near and above treeline, avalanche danger is CONSIDERABLE on all aspects on slopes 35 degrees and steeper. Below treeline, avalanche danger is MODERATE with pockets of CONSIDERABLE danger on all aspects on slopes 35 degrees and steeper. Natural and human triggered storm slab avalanches are possible today along with human triggered loose wet avalanches.

Pockets of MODERATE avalanche danger will form today on slopes steeper than 37 degrees below 8,000' due to daytime warming and rain on snow. Human triggered wet loose avalanches will be possible in some areas.

This morning, avalanche danger is LOW for all elevations and aspects. Pockets of MODERATE avalanche danger may form today on slopes steeper than 37 degrees below 8,000' due to daytime warming and possible rain on snow this afternoon. Small human triggered wet loose avalanches may become possible in some areas.

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This website is owned and maintained by the non-profit arm of the Sierra Avalanche Center. Some of the content is updated by the USDA avalanche forecasters including the forecasts and some observational data. The USDA is not responsible for any advertising, fund-raising events/information, or sponsorship information, or other content not related to the forecasts and the data pertaining to the forecasts.